Anwendungsbeispiele

The Liberty Blue can accomodate a wide range of post-synthetic modifications such as N-terminal acetylation.  Microwave-enhanced SPPS on the Liberty Blue produced nonacetylated and acetylated peptides at 78% and 72% respecitivly with a combined time of 2 hr 16 min and a total of < 200 mL of main wash (DMF) consumed.

Glycopeptides containing O-linked glycans can be synthesized quickly with good purity using microwave-enhanced SPPS. Preparation of a peptide substrate of WbwA (a sialic acid glycosyltransferase), was completed in 3 h 10 min with 68% purity on the Liberty Blue automated microwave peptide synthesizer. Synthesis of an analog of APF (antiproliferative factor) conjugated to the TUS nuclear localization sequence was achieved in 1 h 8 min with 73% purity using the Liberty PRIME automated microwave peptide synthesizer.

Fully automated synthesis of head-to-tail cyclized peptides can be performed rapidly and with excellent purity using the Liberty Blue and Liberty PRIME peptide synthesizers. Microwave SPPS benefits not only the linear assembly but also the subsequent cyclization step with exceptional purity achieved on a variety of difficult biologically important peptides. The one-pot Fmoc SPPS cycles used on the Liberty PRIME provide even further benefit for synthesis time and waste reduction.

This application note demonstrates that His(Boc) is a powerful His derivative that can be effectively coupled at 90 °C, providing favorable crude purity while both decreasing coupling time and dramatically reducing epimerization. Fmoc-His(Boc)-OH is widely available as compared to other epimerization suppressing Nπ protected derivatives while maintaining comparable synthetic performance. In summary, the key benefits of Fmoc-His(Boc)-OH are:

• Commercial bulk availability and competitive price relative to Fmoc-His(Trt)-OH.
• Low epimerization levels at elevated temperatures; coupling temperatures of 50 °C and below make Fmoc-His(Boc)-OH applicable for use in the synthesis of active pharmaceutical ingredients and avoiding complex coupling reagents and conditions.
• Excellent solution stability; comparable to Fmoc-His(π-Mbom)-OH and greater than Fmoc-His(Trt)-OH.